fixed compilation with XCode 10
fixed compilation with XCode 10

fixes https://github.com/OpenSC/OpenSC/issues/1485

hongquan/OpenSC-main,hongquan/OpenSC-main,AktivCo/OpenSC,LudovicRousseau/OpenSC,CardContact/OpenSC,OpenSC/OpenSC,LudovicRousseau/OpenSC,metsma/OpenSC,frankmorgner/OpenSC,fabled/OpenSC,viktorTarasov/OpenSC-SM,fabled/OpenSC,hhonkanen/OpenSC,Jakuje/OpenSC,hongquan/OpenSC-main,rickyepoderi/OpenSC,Jakuje/OpenSC,OpenSC/OpenSC,AktivCo/OpenSC,dengert/OpenSC,Jakuje/OpenSC,hhonkanen/OpenSC,philipWendland/OpenSC,fabled/OpenSC,frankmorgner/OpenSC,AktivCo/OpenSC,metsma/OpenSC,viktorTarasov/OpenSC-SM,rickyepoderi/OpenSC,hhonkanen/OpenSC,philipWendland/OpenSC,philipWendland/OpenSC,CardContact/OpenSC,rickyepoderi/OpenSC,mouse07410/OpenSC,mouse07410/OpenSC,OpenSC/OpenSC,Jakuje/OpenSC,dengert/OpenSC,LudovicRousseau/OpenSC,viktorTarasov/OpenSC-SM,CardContact/OpenSC,metsma/OpenSC,frankmorgner/OpenSC,fabled/OpenSC,dengert/OpenSC,mouse07410/OpenSC,frankmorgner/OpenSC